Noun. Synonym for "Bro." Derived from a stereotypical laugh issuing from a bro or bros at times of excitement or great exclamation. The female version of this is the Teehehe.
"Chahaha! I love college!"
"Chahaha! You wanna go throw some DISC on the QUAD?!"
or
"Wow, that guy is only good at one thing and that's beer pong."
"Well, that's because he's a Chahaha."
"All of their pictures are of when they're passed out and got drawn on!"
"Well yeah, They're Chahahas."